Publications by authors named "Rupa Nagar"
Article Synopsis
- - The text discusses the presence of glycosylphosphatidylinositol (GPI) anchors on proteins in Plasmodium species, particularly focusing on the circumsporozoite protein (CSP), which is vital for the malaria parasite's infective stage.
- - While CSP has been presumed to have a GPI anchor, this research provides biochemical evidence to confirm this assumption through methods like metabolic labeling and mass spectrometry.
- - Specific tests including the presence of myo-inositol, a key component of GPI, solidify the conclusion that CSP is indeed GPI-anchored, reinforcing its significance in malaria biology.
Article Synopsis
- * This study investigates the conversion of D-Glc to D-Ara in the trypanosomatid Crithidia fasciculata, finding that both arms of the pentose phosphate pathway are involved, along with the function of a specific enzyme (GFAT).
- * The research suggests a general pathway for producing D-Ara from D-Glc in eukaryotes, highlighting its roles in synthesizing important compounds, including
Article Synopsis
- The bloodstream form of Trypanosoma brucei has large poly-N-acetyllactosamine (pNAL) chains on glycoproteins, which may be necessary for receptor-mediated endocytosis, and involves glycosyltransferases TbGT10 and TbGT8 in their biosynthesis.
- Researchers created TbGT10 and TbGT8 mutants to assess the impact of these enzymes on pNAL production, finding that although pNAL synthesis was reduced, it was not completely eliminated due to compensatory mechanisms from other glycosyltransferases.
- Interestingly, despite some glycoproteins being significantly affected by the pNAL deficiency, the mutants' transferrin receptor
Article Synopsis
- GPI anchor proteins are a major form of glycosylation in certain species and were primarily studied in the asexual blood stage of the malaria parasite.
- The circumsporozoite protein (CSP), crucial for sporozoite infectivity, was investigated to confirm whether it has a GPI anchor, which was previously assumed but not definitively proven.
- Metabolic labeling and mass-spectrometry techniques provided strong evidence supporting the presence of a GPI anchor on CSP, confirming its important role in the malaria parasite's structure.
Characterization of the major surface glycoconjugates of Trypanosoma theileri.
Mol Biochem Parasitol
December 2023
Trypanosoma theileri maintains a long-term extracellular infection with a low parasitaemia in bovids. The surface of this parasite is predicted to be decorated with several surface molecules including membrane surface proteases (MSPs), trans-sialidases and T. theileri putative surface proteins (TTPSPs).
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- Biofilms are a group lifestyle that microbes use to enhance their chances of survival.
- This study focuses on understanding the biofilm matrix, specifically the pathways involved in synthesizing exopolysaccharides (EPS) that form the matrix.
- The research identifies the initial two crucial steps in the EPS synthesis process, laying the groundwork for further exploration and synthesis of related glycan substrates.
Article Synopsis
- The biosynthesis of GPI-anchored proteins in Trypanosoma brucei requires fatty acid remodeling of GPI precursors before protein transfer in the endoplasmic reticulum.
- Researchers identified the gene Tb927.7.6110, which encodes a protein necessary for GPI-phospholipase A2 (GPI-PLA2) activity in the parasite's procyclic form.
- The absence of this gene in mutant cells led to reduced fatty acid remodeling and smaller GPI anchor sidechains, but this was restored by reintroducing Tb927.7.6110, indicating its critical role in the process.
Article Synopsis
- - The study explores the biosynthesis of an exopolysaccharide, a crucial component of biofilm architecture and function, revealing gaps in current understanding of its biochemical and genetic processes.
- - Researchers identified the first two key steps in the biosynthetic pathway, pinpointing important enzymes (EpsL and EpsD) and their respective substrates involved in the synthesis of the exopolysaccharide.
- - This work lays the groundwork for further detailed studies on biofilm matrix components, ultimately aiding in the manipulation of biofilm formation for various applications in microbiology.
Article Synopsis
- Visceral leishmaniasis is a serious disease caused by the Leishmania donovani parasite, and there is currently no licensed vaccine for it.
- Researchers identified a crucial protein associated with the parasite's ability to adhere to host tissues, which is linked to a specific noncatalytic component of the GPI-mannosyltransferase I complex.
- The study's findings suggest that creating a mutant of this protein might lead to the development of an attenuated live vaccine, as it could provide significant protection against future infections in mouse models.
Article Synopsis
- The parasite Trypanosoma brucei has two forms—bloodstream (BSF) and procyclic (PCF)—that feature different carbohydrate structures linked to their survival and function, with at least 38 possible glycosyltransferase activities.* -
- Researchers investigated the uncharacterized glycosyltransferase gene TbGT10 and discovered it plays a key role in the formation of N-glycans in BSF and GPI anchors in PCF, implying it’s not essential for the parasite's survival despite impacting its fitness.* -
- Analysis showed that the absence of TbGT10 led to significant glycosylation defects, affecting how the parasite interacts with certain antibodies, highlighting its novel
Article Synopsis
- Many eukaryotic cell-surface proteins use glycosylphosphatidylinositol (GPI) moieties to attach to cell membranes, with their biosynthesis starting in the endoplasmic reticulum.
- The enzyme complex responsible for this process includes Gpi3/PIG-A and Gpi2, with the latter being crucial for its activity but whose specific role is unclear.
- Research on Trypanosoma brucei lacking GPI2 revealed reduced GPI transferase activity, changes in complex structure, and underglycosylated surface proteins, indicating GPI2's importance in both the endoplasmic reticulum and Golgi apparatus.
Antimicrobial peptides (AMPs) are novel agents for therapeutic application for their inherent broad spectrum of activities against bacteria, fungi, and viruses, as well as anti-inflammatory, anticancerous, and immunomodulatory activities. This chapter presents an enzymatic method to generate glycovariants of one such antimicrobial peptide, namely enterocin 96, using a bacterial protein O- and S-glycosyltransferase, in vitro.
View Article and Find Full Text PDFKnowledge of glycosylation status and glycan-pattern of proteins are of considerable medical, academic and application interest. ProGlycProt V2.0 (www.
View Article and Find Full Text PDFBloodstream form African trypanosomes are thought to rely exclusively upon glycolysis, using glucose as a substrate, for ATP production. Indeed, the pathway has long been considered a potential therapeutic target to tackle the devastating and neglected tropical diseases caused by these parasites. However, plasma membrane glucose and glycerol transporters are both expressed by trypanosomes and these parasites can infiltrate tissues that contain glycerol.
View Article and Find Full Text PDFGlycosyltransferases are essential tools for in vitro glycoengineering. Bacteria harbor an unexplored variety of protein glycosyltransferases. Here, we describe a peptide glycosyltransferase (EntS) encoded by ORF0417 of Enterococcus faecalis TX0104.
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